The present invention relates to a linear slide ball bearing and a production thereof and a linear slide table incorporating the linear slide ball bearings.
In the sliding portions of numerical controlled machine tools and industrial robots, linear slide ball bearings are used to linearly guide the moving machines, tools, apparatus, and so forth.
In such a linear slide ball bearing, it is desirous making short the speed rise-up time during the linear movement in order to increase speed and making small the force of inertia when the movement stops; consequently, the weight of a sliding table must be minimized. However, owing to the fact that high rigidity is required particularly for the portion where a load ball groove is formed in the slide table, consideration can be given to the use of material offering excellent rigidity for the formation of the portion where the load ball groove is provided and of material relatively light in weight for the formation of the remaining portion so as to couple both the portions in one body with a coupling bolt. However, the problem is that reduced productivity will make such a combination costly as screw tapping is needed in this case.
Moreover, because importance is normally attached to the length of life of such a linear slide ball bearing, the bearing when it is fitted in a linear slide table needs pressurizing to a great extent, whereas only minor pressurization should be applied to the bearing used when light sliding is particularly necessary as it is used for a measuring instrument, etc.; in other words, since the efficiency required differs depending on its use and the operating condition, pressurization applicable to the bearing varies in magnitude. For this reason, it will be extremely convenient if varieties of requirements are satisfiable through simple adjusting operation.